Timberwolf chipper blades

[33bk]

The new reversible blades on the Timberwolf chipper come with a curve on the cutting education ge ,

I’ve just got mine back from being sharped from a big company and they’ve Take the curve off ? Is this normal before I phone up to have a moan ? 

 

Cheers ears mike 

[aspenarb]

I sharpen my own TW knives Mike, I have done both hollow and straight grinds on them. The hollow ground knives are definitely better on conny and willow, cant say there is much in it on hardwoods.

 

You get a finer cutting edge on the hollow ground vs the straight, exaggerated below but you can see whats going on.

 

Bob

 

[33bk]

Cheers bob , from the bit of research I’ve done it’s just a personal preference really I think 

now there straight they’ll probably stay straight.

mike 

 

[Mick Dempsey]

This has been raised before, I used both and never noticed a difference (this was on an old 150)

 

However TW chimed in and said that that the hollow blades are better for the machine (main rotor bearings etc.)

 

How much difference it really makes.... I dunno.

[Ty Korrigan]

I'd suggest that might be an old excuse for not having greaseable bearings on some models...

   Stuart

[s o c]

Flat here.

i get mine sharpened by saw doctor at large sawmill.

hollow ground definitely chip better but don’t stay sharp as long.

after half a days chipping, no difference imo.

also, with flat ground there’s less ground off to get sharp again as edge not as easily damaged.

[GA Groundcare]

If the grinding stone is 90 degree to the chipper blade on the blade grinder = "hollow ground" 

If the grinding stone is parallel to the chipper blade on the blade grinder = "flat ground"

 

We flat grind.

Edited July 4, 2018 by GA Groundcare

[J Holtby]

Making a jig up, anyone know what radius is the hollow grind on tw150 blades?

[woody paul]

Just use your current blades as templates shouldn't be far out. 

Radius is set by grind stone. 

Edited December 31, 2021 by woody paul

[john87]

If it was not important to have them hollow ground, timber wolf would not bother, as presumably they want them ground to a set radius as opposed to whatever diameter your grinding wheel has worn down to..

 

Funnily enough, i have got a proper tool and cutter grinder here. I wonder if i should have a go at doing one myself..

 

john..